SMA SC 500HE-20 Maintenance Manua - Manual (Page 18)

6 Maintenance Under Voltage-Free Conditions SMA Solar Technology AG
18 SC500-800HE20-WH-en-10 Maintenance Manual
6 Maintenance Under Voltage-Free Conditions
6.1 Disconnecting the Inverter
Before doing any maintenance work, disconnect the inverter from all voltage sources as described in
this section.
1. Switch the inverter to "Stop".
2. Disconnect the AC voltage of the medium-voltage transformer externally.
3. Disconnect the DC voltage in the main distributor (e.g. Sunny Main Box) or the sub-distributor
(e.g. Sunny String-Monitor).
4. Switch off the AC circuit breaker.
5. Disconnect the external voltage supply externally.
6. Disconnect any additional external voltage.
7. Switch off the miniature circuit-breaker of the
external voltage supply and if necessary,
disconnect the internal power supply transformer.
%"/(&3
Electric shock due to live voltage.
The components of the Sunny Central are energised. Touching components of the Sunny Central
may result in death or severe injuries.
• Before performing any work on the Sunny Central, disconnect the inverter and ensure that it
cannot be reconnected.
• After disconnecting the inverter, wait at least 15 minutes until the inverter capacitors have
discharged completely.
• Ensure that no voltage is present.
Person authorised to operate the medium-voltage transformer
Only a duly authorised person may connect or disconnect the AC voltage of the
medium-voltage transformer.